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    <ul>
        <li>
            <a href="cources.html" target="content_frame">Courses</a>
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        <li>
            <a href="book1.html" target="content_frame">Creating and Selecting a Database</a>
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        <li>
            <a href="book2.html" target="content_frame">Creating a Table</a>
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        <li>
            <a href="book3.html" target="content_frame">Loading Data into a Table</a>
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